Brazing to fabricate certain components can present challenges. Some components can have joints between materials and/or portions of the component that require them to be secured to one another. Such components are present, for example, in tube-to-plate components, such as heat exchangers and micromixers.
Prior attempts to braze large amounts of such joints at one time (for example, between up to about 100 tubes being brazed to between about 2, 4, or more plates) have resulted in substantial and costly re-work. In part, such re-work is due to the tight tolerances (for example, gap ranges for nickel brazing being between about 0.0005 inches to about 0.004 inches). It is difficult to maintain tube and plate machining operations within these tolerances. Due to the tight tolerances, introducing additional sources of variation can be undesirable.
Due to the machining operations preventing the introduction of additional variation, additional variation introduced by brazing is especially undesirable. Known brazing processes use braze paste to secure tubes to plates. However, such braze paste must be manually applied, which can be expensive, can result in inconsistent placement of braze paste, can result in inconsistent quantity of the braze paste, and can often only be applied to one side of a component, which can be dependent upon capillary action of the braze paste flowing through a gap. The flow is, thus, dependent upon gap size, which can also vary. These inconsistencies can lead to variances exceeding defined tolerances. To remedy such variances, expensive re-brazing steps can be employed. Avoiding such re-brazing steps would be desirable.
A brazing process and a brazed component that do not suffer from one or more of the above drawbacks would be desirable in the art.